diff options
| author | Lv Yunlong <lyl2019@mail.ustc.edu.cn> | 2021-03-28 00:30:29 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-04-16 12:00:21 +0200 |
| commit | c8728e4d18716b776f2b2fd5c88763db5d76dbc7 (patch) | |
| tree | 967f84236912e91e76a1b8880e87e600c7c7c38f /net/tipc | |
| parent | 054e8535c63a94c68fc9706afbd32b1d91bf1d45 (diff) | |
net:tipc: Fix a double free in tipc_sk_mcast_rcv
[ Upstream commit 6bf24dc0cc0cc43b29ba344b66d78590e687e046 ]
In the if(skb_peek(arrvq) == skb) branch, it calls __skb_dequeue(arrvq) to get
the skb by skb = skb_peek(arrvq). Then __skb_dequeue() unlinks the skb from arrvq
and returns the skb which equals to skb_peek(arrvq). After __skb_dequeue(arrvq)
finished, the skb is freed by kfree_skb(__skb_dequeue(arrvq)) in the first time.
Unfortunately, the same skb is freed in the second time by kfree_skb(skb) after
the branch completed.
My patch removes kfree_skb() in the if(skb_peek(arrvq) == skb) branch, because
this skb will be freed by kfree_skb(skb) finally.
Fixes: cb1b728096f54 ("tipc: eliminate race condition at multicast reception")
Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net/tipc')
| -rw-r--r-- | net/tipc/socket.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/tipc/socket.c b/net/tipc/socket.c index 65171f8e8c45..0e5bb03c6425 100644 --- a/net/tipc/socket.c +++ b/net/tipc/socket.c @@ -763,7 +763,7 @@ void tipc_sk_mcast_rcv(struct net *net, struct sk_buff_head *arrvq, spin_lock_bh(&inputq->lock); if (skb_peek(arrvq) == skb) { skb_queue_splice_tail_init(&tmpq, inputq); - kfree_skb(__skb_dequeue(arrvq)); + __skb_dequeue(arrvq); } spin_unlock_bh(&inputq->lock); __skb_queue_purge(&tmpq); |